BETTII - the Balloon Experimental Twin Telescope for Far Infrared Interferometry

Lead Research Organisation: University College London
Department Name: Physics and Astronomy

Abstract

(as per submitted Joint proposal - MJG_BETTII_PRD)

More than half of the energy generated in the Universe since the big bang now exists in the form of electromagnetic
radiation in the far infrared part of the spectrum - wavelengths a few hundred times longer than those of visible light. Much
of the energy emitted by developing stars and young stars is absorbed by the clouds of gas and dust in which they form,
and re-radiated in the far infrared. So if we want to understand the birth processes of stars in our own galaxy today, or to
investigate how galaxies grow and develop (through star-formation), we need to make observations in the far infrared. In
recent years, huge advances have been made by telescopes in space and operating on high altitude balloons in our
endeavours to gain knowledge of the details of star and planetary system formation and the history of galaxies like our own
Milky Way. But astronomy at far infrared wavelengths has a long way to go before we will be able to take pictures with
similar quality to that obtained by optical telescopes at shorter wavelengths and by arrays of radio telescopes at longer
wavelengths.
Observations have to be made from space or from high altitude because the atmosphere is strongly absorbing in this part
of the spectrum. That makes it difficult to use large ground-based telescopes. In addition, the technique of "interferometry",
used in the radio region of combining the beams from number of smaller telescopes to make an image as good as that
from a much larger one, has not yet been perfected in the far infrared. So at present, the image quality of observations in
the far infrared is not nearly as good as astronomers need to get a better view of stars and galaxies and their origins.
In this project we will make a big advance by building the first scientific interferometer working in the far infrared, flying it on
a high altitude balloon, and making observations of both of star forming regions in our galaxy and also of active galaxies
harbouring massive black holes at their centres, to learn more about how stars form in clusters and how black holes
interact with the galaxies they inhabit. These pioneering measurements will be the highest quality far infrared observations
ever, in terms of our ability to discern fine details in the image. Besides giving us new scientific insights, they will allow us
to perfect and demonstrate the technology needed to build a more ambitions and powerful instrument in the future, perhaps
a space-borne system, to provide even better observations. The scientific importance of such an observatory has been
recognised by both NASA and by the European Space Agency, who are considering space missions of this type. However,
the necessary technology and expertise is not available yet, and this work will make a big contribution to establishing our
capability to fly such a mission.

Planned Impact

(as per submitted Joint proposal - MJG_BETTII_PRD)

In addition to the astronomical community through new and pioneering observations, the beneficiaries of our impact
activities associated with this project will include:
The European space science programme: through the development of components and techniques relevant to future
space astronomy missions. This project, besides carrying out new astronomical observations, will be a technical pathfinder
relevant to a possible future ESA Science Programme mission.
The image of the UK as an international partner in front-rank scientific projects, capable of providing unique technical and
scientific capabilities: The status of the UK as a country at the forefront of science and R&D relies upon the establishment
of international programmes and partnerships involving the best researchers and institutes in other countries. Here we will
collaborate with NASA Goddard Space Flight Center, using our unique technical capabilities to enable new research.
The local and national economy: through
(i) the operation of a high-tech SME based at Cardiff (QMC Instruments Ltd.) which employs five people,
(ii) the training of young people (PhD students and postdocs) who develop high-level skills (in research techniques, IT,
materials science and processes, etc.) and most of whom go on to get jobs in the industrial, commercial or educational
sectors; and
(iii) the inspiration of young people to pursue educational opportunities and careers in STEM through our outreach
programmes. In addition, there may be future major benefits for the UK space industry in the longer term, through the
fostering of UK leadership within Europe in instrumentation technology important for future space missions. This may lever
significant high-tech industrial involvement on the part of UK industry in the context of a future mission and its industrial
programme.
The experimental scientific community (in numerous fields: through the availability of advanced components and systems
in the THz regime, enabling new scientific research, under either collaborative or commercial arrangements. QMC
Instruments Ltd. commercialises technology developed by the Cardiff AIG, and serves a largely export market which
encompasses provision of a wide variety of infrared and THz components and systems to the worldwide academic
research community (astronomy, chemistry, plasma physics, THz lab spectroscopy) and endeavours addressing the grand
challenge of energy research (plasma fusion diagnostics). In addition, ten Cardiff group has a long-standing record of
applying technology developed for FIR astronomy in the field of Earth Observing, enabling investigations into both
stratospheric chemistry and the influence of clouds on the Earth's radiation budget.
The general public: through the culturally and intellectually valuable contemplation and understanding of the physical world
and our place in it. We regard this as an important motivation for all our research, and pursue an active programme in this
area (as described in the Pathways to Impact Statement).
 
Description Through this activity we explored methods to combine input beams from two telescopes
to obtain a spatial resolution comparable to that of a telescope with a size comparable to
the distance of the two telescopes used. Similarly to radio interferometry (but with a different technique),
this will allow to hugely increase resolving power in astronomy without building gigantic telescopes.
This activity supported the design/build and testing of a US-led prototype that flew on a high altitude balloon
ahead of potential future prototypes for space.
Furthermore during this activity, we explored the application of this technique (used in the Far-Infrared)
to room-temperature detectors in the Mid-IR and with additional imaging capabilities.
Exploitation Route This technique could allow the improvement of ground resolution in Earth Observing if applied to Low-Earth orbit satellites, without having to resolve to much larger telescope sizes. Additional applications could be found where detection of smaller objects from large distances are required. The technique can be adapted on the primary need for any given application (photometric or spectroscopic).
Sectors Aerospace, Defence and Marine,Environment,Other

 
Description FP7-FISICA
Amount € 1,996,586 (EUR)
Funding ID FP7-312818 
Organisation European Commission 
Sector Public
Country European Union (EU)
Start 01/2013 
End 12/2015
 
Description BETTII Collaboration 
Organisation Cardiff University
Department School of Physics and Astronomy
Country United Kingdom 
Sector Academic/University 
PI Contribution This collaboration revolves on the exchange of information related to hardware build and characteristics of the instrumentation involved and the relevant modelling and simulations.
Collaborator Contribution We provide optical modelling, simulations of instrument performance, material testing and will ultimately provide a calibration source for the instrument.
Impact See description in Key findings.
Start Year 2013
 
Description BETTII Collaboration 
Organisation National Aeronautics and Space Administration (NASA)
Department Goddard Space Flight Center
Country United States 
Sector Public 
PI Contribution This collaboration revolves on the exchange of information related to hardware build and characteristics of the instrumentation involved and the relevant modelling and simulations.
Collaborator Contribution We provide optical modelling, simulations of instrument performance, material testing and will ultimately provide a calibration source for the instrument.
Impact See description in Key findings.
Start Year 2013
 
Description BETTII Collaboration 
Organisation University of Maryland
Country United States 
Sector Academic/University 
PI Contribution This collaboration revolves on the exchange of information related to hardware build and characteristics of the instrumentation involved and the relevant modelling and simulations.
Collaborator Contribution We provide optical modelling, simulations of instrument performance, material testing and will ultimately provide a calibration source for the instrument.
Impact See description in Key findings.
Start Year 2013